xref: /dragonfly/sys/net/dummynet/ip_dummynet.c (revision a007903a4ec12165bffac7879c47c3b30bfbddda)
1 /*
2  * Copyright (c) 1998-2002 Luigi Rizzo, Universita` di Pisa
3  * Portions Copyright (c) 2000 Akamba Corp.
4  * All rights reserved
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD: src/sys/netinet/ip_dummynet.c,v 1.24.2.22 2003/05/13 09:31:06 maxim Exp $
28  */
29 
30 #include "opt_ipdn.h"
31 
32 /*
33  * This module implements IP dummynet, a bandwidth limiter/delay emulator.
34  * Description of the data structures used is in ip_dummynet.h
35  * Here you mainly find the following blocks of code:
36  *  + variable declarations;
37  *  + heap management functions;
38  *  + scheduler and dummynet functions;
39  *  + configuration and initialization.
40  *
41  * Most important Changes:
42  *
43  * 011004: KLDable
44  * 010124: Fixed WF2Q behaviour
45  * 010122: Fixed spl protection.
46  * 000601: WF2Q support
47  * 000106: Large rewrite, use heaps to handle very many pipes.
48  * 980513: Initial release
49  */
50 
51 #include <sys/param.h>
52 #include <sys/kernel.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/socketvar.h>
56 #include <sys/sysctl.h>
57 #include <sys/systimer.h>
58 #include <sys/thread2.h>
59 
60 #include <net/ethernet.h>
61 #include <net/netmsg2.h>
62 #include <net/netisr2.h>
63 #include <net/route.h>
64 
65 #include <net/if.h>
66 #include <netinet/in_var.h>
67 #include <netinet/ip_var.h>
68 
69 #include <net/dummynet/ip_dummynet.h>
70 
71 #ifdef DUMMYNET_DEBUG
72 #define DPRINTF(fmt, ...)     kprintf(fmt, __VA_ARGS__)
73 #else
74 #define DPRINTF(fmt, ...)     ((void)0)
75 #endif
76 
77 #ifndef DN_CALLOUT_FREQ_MAX
78 #define DN_CALLOUT_FREQ_MAX   10000
79 #endif
80 
81 /*
82  * The maximum/minimum hash table size for queues.
83  * These values must be a power of 2.
84  */
85 #define DN_MIN_HASH_SIZE      4
86 #define DN_MAX_HASH_SIZE      65536
87 
88 /*
89  * Some macros are used to compare key values and handle wraparounds.
90  * MAX64 returns the largest of two key values.
91  */
92 #define DN_KEY_LT(a, b)                 ((int64_t)((a) - (b)) < 0)
93 #define DN_KEY_LEQ(a, b)      ((int64_t)((a) - (b)) <= 0)
94 #define DN_KEY_GT(a, b)                 ((int64_t)((a) - (b)) > 0)
95 #define DN_KEY_GEQ(a, b)      ((int64_t)((a) - (b)) >= 0)
96 #define MAX64(x, y)           ((((int64_t)((y) - (x))) > 0) ? (y) : (x))
97 
98 #define DN_NR_HASH_MAX                  16
99 #define DN_NR_HASH_MASK                 (DN_NR_HASH_MAX - 1)
100 #define DN_NR_HASH(nr)                  \
101           ((((nr) >> 12) ^ ((nr) >> 8) ^ ((nr) >> 4) ^ (nr)) & DN_NR_HASH_MASK)
102 
103 MALLOC_DEFINE(M_DUMMYNET, "dummynet", "dummynet heap");
104 
105 extern int          ip_dn_cpu;
106 
107 static dn_key       curr_time = 0;                /* current simulation time */
108 static int          dn_hash_size = 64;  /* default hash size */
109 static int          pipe_expire = 1;    /* expire queue if empty */
110 static int          dn_max_ratio = 16;  /* max queues/buckets ratio */
111 
112 /*
113  * Statistics on number of queue searches and search steps
114  */
115 static int          searches;
116 static int          search_steps;
117 
118 /*
119  * RED parameters
120  */
121 static int          red_lookup_depth = 256;       /* default lookup table depth */
122 static int          red_avg_pkt_size = 512;       /* default medium packet size */
123 static int          red_max_pkt_size = 1500;/* default max packet size */
124 
125 /*
126  * Three heaps contain queues and pipes that the scheduler handles:
127  *
128  *  + ready_heap    contains all dn_flow_queue related to fixed-rate pipes.
129  *  + wfq_ready_heap          contains the pipes associated with WF2Q flows
130  *  + extract_heap  contains pipes associated with delay lines.
131  */
132 static struct dn_heap         ready_heap;
133 static struct dn_heap         extract_heap;
134 static struct dn_heap         wfq_ready_heap;
135 
136 static struct dn_pipe_head    pipe_table[DN_NR_HASH_MAX];
137 static struct dn_flowset_head flowset_table[DN_NR_HASH_MAX];
138 
139 /*
140  * Variables for dummynet systimer
141  */
142 static struct netmsg_base dn_netmsg;
143 static struct systimer        dn_clock;
144 #ifdef _KERNEL_VIRTUAL
145 static int                    dn_hz = 100;
146 #else
147 static int                    dn_hz = 1000;
148 #endif
149 static int                    dn_count;
150 static int                    dn_running;
151 static struct lock  dn_lock = LOCK_INITIALIZER("dnlk", 0, 0);
152 
153 static int          sysctl_dn_hz(SYSCTL_HANDLER_ARGS);
154 
155 SYSCTL_DECL(_net_inet_ip_dummynet);
156 
157 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, hash_size, CTLFLAG_RW,
158              &dn_hash_size, 0, "Default hash table size");
159 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, curr_time, CTLFLAG_RD,
160              &curr_time, 0, "Current tick");
161 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, expire, CTLFLAG_RW,
162              &pipe_expire, 0, "Expire queue if empty");
163 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, max_chain_len, CTLFLAG_RW,
164              &dn_max_ratio, 0, "Max ratio between dynamic queues and buckets");
165 
166 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, ready_heap, CTLFLAG_RD,
167              &ready_heap.size, 0, "Size of ready heap");
168 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, extract_heap, CTLFLAG_RD,
169              &extract_heap.size, 0, "Size of extract heap");
170 
171 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, searches, CTLFLAG_RD,
172              &searches, 0, "Number of queue searches");
173 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, search_steps, CTLFLAG_RD,
174              &search_steps, 0, "Number of queue search steps");
175 
176 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_lookup_depth, CTLFLAG_RD,
177              &red_lookup_depth, 0, "Depth of RED lookup table");
178 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_avg_pkt_size, CTLFLAG_RD,
179              &red_avg_pkt_size, 0, "RED Medium packet size");
180 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_max_pkt_size, CTLFLAG_RD,
181              &red_max_pkt_size, 0, "RED Max packet size");
182 
183 SYSCTL_PROC(_net_inet_ip_dummynet, OID_AUTO, hz, CTLTYPE_INT | CTLFLAG_RW,
184               0, 0, sysctl_dn_hz, "I", "Dummynet callout frequency");
185 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, running, CTLFLAG_RD,
186              &dn_running, 0, "Dummynet Active");
187 SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, count, CTLFLAG_RD,
188              &dn_count, 0, "Dummynet pipe+flow count");
189 
190 static int          heap_init(struct dn_heap *, int);
191 static int          heap_insert(struct dn_heap *, dn_key, void *);
192 static void         heap_extract(struct dn_heap *, void *);
193 
194 static void         transmit_event(struct dn_pipe *);
195 static void         ready_event(struct dn_flow_queue *);
196 static void         ready_event_wfq(struct dn_pipe *);
197 
198 static int          config_pipe(struct dn_ioc_pipe *);
199 static void         dummynet_flush(void);
200 
201 static void         dummynet_clock(systimer_t, int, struct intrframe *);
202 static void         dummynet(netmsg_t);
203 
204 static struct dn_pipe *dn_find_pipe(int);
205 static struct dn_flow_set *dn_locate_flowset(int, int);
206 
207 typedef void        (*dn_pipe_iter_t)(struct dn_pipe *, void *);
208 static void         dn_iterate_pipe(dn_pipe_iter_t, void *);
209 
210 typedef void        (*dn_flowset_iter_t)(struct dn_flow_set *, void *);
211 static void         dn_iterate_flowset(dn_flowset_iter_t, void *);
212 
213 static ip_dn_io_t   dummynet_io;
214 static ip_dn_ctl_t  dummynet_ctl;
215 
216 /*
217  * Heap management functions.
218  *
219  * In the heap, first node is element 0. Children of i are 2i+1 and 2i+2.
220  * Some macros help finding parent/children so we can optimize them.
221  *
222  * heap_init() is called to expand the heap when needed.
223  * Increment size in blocks of 16 entries.
224  * XXX failure to allocate a new element is a pretty bad failure
225  * as we basically stall a whole queue forever!!
226  * Returns 1 on error, 0 on success
227  */
228 #define HEAP_FATHER(x)                  (((x) - 1) / 2)
229 #define HEAP_LEFT(x)                    (2*(x) + 1)
230 #define HEAP_IS_LEFT(x)                 ((x) & 1)
231 #define HEAP_RIGHT(x)                   (2*(x) + 2)
232 #define HEAP_SWAP(a, b, buffer)         { buffer = a; a = b; b = buffer; }
233 #define HEAP_INCREMENT                  15
234 
235 static int
heap_init(struct dn_heap * h,int new_size)236 heap_init(struct dn_heap *h, int new_size)
237 {
238     struct dn_heap_entry *p;
239 
240     if (h->size >= new_size) {
241           kprintf("%s, Bogus call, have %d want %d\n", __func__,
242                     h->size, new_size);
243           return 0;
244     }
245 
246     new_size = (new_size + HEAP_INCREMENT) & ~HEAP_INCREMENT;
247     p = kmalloc(new_size * sizeof(*p), M_DUMMYNET, M_WAITOK | M_ZERO);
248     if (h->size > 0) {
249           bcopy(h->p, p, h->size * sizeof(*p));
250           kfree(h->p, M_DUMMYNET);
251     }
252     h->p = p;
253     h->size = new_size;
254     return 0;
255 }
256 
257 /*
258  * Insert element in heap. Normally, p != NULL, we insert p in
259  * a new position and bubble up.  If p == NULL, then the element is
260  * already in place, and key is the position where to start the
261  * bubble-up.
262  * Returns 1 on failure (cannot allocate new heap entry)
263  *
264  * If offset > 0 the position (index, int) of the element in the heap is
265  * also stored in the element itself at the given offset in bytes.
266  */
267 #define SET_OFFSET(heap, node) \
268     if (heap->offset > 0) \
269           *((int *)((char *)(heap->p[node].object) + heap->offset)) = node;
270 
271 /*
272  * RESET_OFFSET is used for sanity checks. It sets offset to an invalid value.
273  */
274 #define RESET_OFFSET(heap, node) \
275     if (heap->offset > 0) \
276           *((int *)((char *)(heap->p[node].object) + heap->offset)) = -1;
277 
278 static int
heap_insert(struct dn_heap * h,dn_key key1,void * p)279 heap_insert(struct dn_heap *h, dn_key key1, void *p)
280 {
281     int son;
282 
283     if (p == NULL) {          /* Data already there, set starting point */
284           son = key1;
285     } else {                  /* Insert new element at the end, possibly resize */
286           son = h->elements;
287           if (son == h->size) { /* Need resize... */
288               if (heap_init(h, h->elements + 1))
289                     return 1; /* Failure... */
290           }
291           h->p[son].object = p;
292           h->p[son].key = key1;
293           h->elements++;
294     }
295 
296     while (son > 0) {         /* Bubble up */
297           int father = HEAP_FATHER(son);
298           struct dn_heap_entry tmp;
299 
300           if (DN_KEY_LT(h->p[father].key, h->p[son].key))
301               break; /* Found right position */
302 
303           /* 'son' smaller than 'father', swap and repeat */
304           HEAP_SWAP(h->p[son], h->p[father], tmp);
305           SET_OFFSET(h, son);
306           son = father;
307     }
308     SET_OFFSET(h, son);
309     return 0;
310 }
311 
312 /*
313  * Remove top element from heap, or obj if obj != NULL
314  */
315 static void
heap_extract(struct dn_heap * h,void * obj)316 heap_extract(struct dn_heap *h, void *obj)
317 {
318     int child, father, max = h->elements - 1;
319 
320     if (max < 0) {
321           kprintf("warning, extract from empty heap 0x%p\n", h);
322           return;
323     }
324 
325     father = 0; /* Default: move up smallest child */
326     if (obj != NULL) { /* Extract specific element, index is at offset */
327           if (h->offset <= 0)
328               panic("%s from middle not supported on this heap!!!", __func__);
329 
330           father = *((int *)((char *)obj + h->offset));
331           if (father < 0 || father >= h->elements) {
332               panic("%s father %d out of bound 0..%d", __func__,
333                       father, h->elements);
334           }
335     }
336     RESET_OFFSET(h, father);
337 
338     child = HEAP_LEFT(father);                    /* Left child */
339     while (child <= max) {              /* Valid entry */
340           if (child != max && DN_KEY_LT(h->p[child + 1].key, h->p[child].key))
341               child = child + 1;                  /* Take right child, otherwise left */
342           h->p[father] = h->p[child];
343           SET_OFFSET(h, father);
344           father = child;
345           child = HEAP_LEFT(child);     /* Left child for next loop */
346     }
347     h->elements--;
348     if (father != max) {
349           /*
350            * Fill hole with last entry and bubble up, reusing the insert code
351            */
352           h->p[father] = h->p[max];
353           heap_insert(h, father, NULL); /* This one cannot fail */
354     }
355 }
356 
357 /*
358  * heapify() will reorganize data inside an array to maintain the
359  * heap property.  It is needed when we delete a bunch of entries.
360  */
361 static void
heapify(struct dn_heap * h)362 heapify(struct dn_heap *h)
363 {
364     int i;
365 
366     for (i = 0; i < h->elements; i++)
367           heap_insert(h, i , NULL);
368 }
369 
370 /*
371  * Cleanup the heap and free data structure
372  */
373 static void
heap_free(struct dn_heap * h)374 heap_free(struct dn_heap *h)
375 {
376     if (h->size > 0)
377           kfree(h->p, M_DUMMYNET);
378     bzero(h, sizeof(*h));
379 }
380 
381 /*
382  * --- End of heap management functions ---
383  */
384 
385 /*
386  * Scheduler functions:
387  *
388  * transmit_event() is called when the delay-line needs to enter
389  * the scheduler, either because of existing pkts getting ready,
390  * or new packets entering the queue.  The event handled is the delivery
391  * time of the packet.
392  *
393  * ready_event() does something similar with fixed-rate queues, and the
394  * event handled is the finish time of the head pkt.
395  *
396  * ready_event_wfq() does something similar with WF2Q queues, and the
397  * event handled is the start time of the head pkt.
398  *
399  * In all cases, we make sure that the data structures are consistent
400  * before passing pkts out, because this might trigger recursive
401  * invocations of the procedures.
402  */
403 static void
transmit_event(struct dn_pipe * pipe)404 transmit_event(struct dn_pipe *pipe)
405 {
406     struct dn_pkt *pkt;
407 
408     while ((pkt = TAILQ_FIRST(&pipe->p_queue)) &&
409              DN_KEY_LEQ(pkt->output_time, curr_time)) {
410           TAILQ_REMOVE(&pipe->p_queue, pkt, dn_next);
411           ip_dn_packet_redispatch(pkt);
412     }
413 
414     /*
415      * If there are leftover packets, put into the heap for next event
416      */
417     if ((pkt = TAILQ_FIRST(&pipe->p_queue)) != NULL) {
418           /*
419            * XXX should check errors on heap_insert, by draining the
420            * whole pipe and hoping in the future we are more successful
421            */
422           heap_insert(&extract_heap, pkt->output_time, pipe);
423     }
424 }
425 
426 /*
427  * The following macro computes how many ticks we have to wait
428  * before being able to transmit a packet. The credit is taken from
429  * either a pipe (WF2Q) or a flow_queue (per-flow queueing)
430  */
431 #define SET_TICKS(pkt, q, p)  \
432     (pkt->dn_m->m_pkthdr.len*8*dn_hz - (q)->numbytes + p->bandwidth - 1 ) / \
433               p->bandwidth;
434 
435 /*
436  * Extract pkt from queue, compute output time (could be now)
437  * and put into delay line (p_queue)
438  */
439 static void
move_pkt(struct dn_pkt * pkt,struct dn_flow_queue * q,struct dn_pipe * p,int len)440 move_pkt(struct dn_pkt *pkt, struct dn_flow_queue *q,
441            struct dn_pipe *p, int len)
442 {
443     TAILQ_REMOVE(&q->queue, pkt, dn_next);
444     q->len--;
445     q->len_bytes -= len;
446 
447     pkt->output_time = curr_time + p->delay;
448 
449     TAILQ_INSERT_TAIL(&p->p_queue, pkt, dn_next);
450 }
451 
452 /*
453  * ready_event() is invoked every time the queue must enter the
454  * scheduler, either because the first packet arrives, or because
455  * a previously scheduled event fired.
456  * On invokation, drain as many pkts as possible (could be 0) and then
457  * if there are leftover packets reinsert the pkt in the scheduler.
458  */
459 static void
ready_event(struct dn_flow_queue * q)460 ready_event(struct dn_flow_queue *q)
461 {
462     struct dn_pkt *pkt;
463     struct dn_pipe *p = q->fs->pipe;
464     int p_was_empty;
465 
466     if (p == NULL) {
467           kprintf("ready_event- pipe is gone\n");
468           return;
469     }
470     p_was_empty = TAILQ_EMPTY(&p->p_queue);
471 
472     /*
473      * Schedule fixed-rate queues linked to this pipe:
474      * Account for the bw accumulated since last scheduling, then
475      * drain as many pkts as allowed by q->numbytes and move to
476      * the delay line (in p) computing output time.
477      * bandwidth==0 (no limit) means we can drain the whole queue,
478      * setting len_scaled = 0 does the job.
479      */
480     q->numbytes += (curr_time - q->sched_time) * p->bandwidth;
481     while ((pkt = TAILQ_FIRST(&q->queue)) != NULL) {
482           int len = pkt->dn_m->m_pkthdr.len;
483           int len_scaled = p->bandwidth ? len*8*dn_hz : 0;
484 
485           if (len_scaled > q->numbytes)
486               break;
487           q->numbytes -= len_scaled;
488           move_pkt(pkt, q, p, len);
489     }
490 
491     /*
492      * If we have more packets queued, schedule next ready event
493      * (can only occur when bandwidth != 0, otherwise we would have
494      * flushed the whole queue in the previous loop).
495      * To this purpose we record the current time and compute how many
496      * ticks to go for the finish time of the packet.
497      */
498     if ((pkt = TAILQ_FIRST(&q->queue)) != NULL) {
499           /* This implies bandwidth != 0 */
500           dn_key t = SET_TICKS(pkt, q, p); /* ticks i have to wait */
501 
502           q->sched_time = curr_time;
503 
504           /*
505            * XXX should check errors on heap_insert, and drain the whole
506            * queue on error hoping next time we are luckier.
507            */
508           heap_insert(&ready_heap, curr_time + t, q);
509     } else {        /* RED needs to know when the queue becomes empty */
510           q->q_time = curr_time;
511           q->numbytes = 0;
512     }
513 
514     /*
515      * If the delay line was empty call transmit_event(p) now.
516      * Otherwise, the scheduler will take care of it.
517      */
518     if (p_was_empty)
519           transmit_event(p);
520 }
521 
522 /*
523  * Called when we can transmit packets on WF2Q queues.  Take pkts out of
524  * the queues at their start time, and enqueue into the delay line.
525  * Packets are drained until p->numbytes < 0.  As long as
526  * len_scaled >= p->numbytes, the packet goes into the delay line
527  * with a deadline p->delay.  For the last packet, if p->numbytes < 0,
528  * there is an additional delay.
529  */
530 static void
ready_event_wfq(struct dn_pipe * p)531 ready_event_wfq(struct dn_pipe *p)
532 {
533     int p_was_empty = TAILQ_EMPTY(&p->p_queue);
534     struct dn_heap *sch = &p->scheduler_heap;
535     struct dn_heap *neh = &p->not_eligible_heap;
536 
537     p->numbytes += (curr_time - p->sched_time) * p->bandwidth;
538 
539     /*
540      * While we have backlogged traffic AND credit, we need to do
541      * something on the queue.
542      */
543     while (p->numbytes >= 0 && (sch->elements > 0 || neh->elements > 0)) {
544           if (sch->elements > 0) { /* Have some eligible pkts to send out */
545               struct dn_flow_queue *q = sch->p[0].object;
546               struct dn_pkt *pkt = TAILQ_FIRST(&q->queue);
547               struct dn_flow_set *fs = q->fs;
548               uint64_t len = pkt->dn_m->m_pkthdr.len;
549               int len_scaled = p->bandwidth ? len*8*dn_hz : 0;
550 
551               heap_extract(sch, NULL);  /* Remove queue from heap */
552               p->numbytes -= len_scaled;
553               move_pkt(pkt, q, p, len);
554 
555               p->V += (len << MY_M) / p->sum;     /* Update V */
556               q->S = q->F;                        /* Update start time */
557 
558               if (q->len == 0) {        /* Flow not backlogged any more */
559                     fs->backlogged--;
560                     heap_insert(&p->idle_heap, q->F, q);
561               } else {                  /* Still backlogged */
562                     /*
563                      * Update F and position in backlogged queue, then
564                      * put flow in not_eligible_heap (we will fix this later).
565                      */
566                     len = TAILQ_FIRST(&q->queue)->dn_m->m_pkthdr.len;
567                     q->F += (len << MY_M) / (uint64_t)fs->weight;
568                     if (DN_KEY_LEQ(q->S, p->V))
569                         heap_insert(neh, q->S, q);
570                     else
571                         heap_insert(sch, q->F, q);
572               }
573           }
574 
575           /*
576            * Now compute V = max(V, min(S_i)).  Remember that all elements in
577            * sch have by definition S_i <= V so if sch is not empty, V is surely
578            * the max and we must not update it.  Conversely, if sch is empty
579            * we only need to look at neh.
580            */
581           if (sch->elements == 0 && neh->elements > 0)
582               p->V = MAX64(p->V, neh->p[0].key);
583 
584           /*
585            * Move from neh to sch any packets that have become eligible
586            */
587           while (neh->elements > 0 && DN_KEY_LEQ(neh->p[0].key, p->V)) {
588               struct dn_flow_queue *q = neh->p[0].object;
589 
590               heap_extract(neh, NULL);
591               heap_insert(sch, q->F, q);
592           }
593     }
594 
595     if (sch->elements == 0 && neh->elements == 0 && p->numbytes >= 0 &&
596           p->idle_heap.elements > 0) {
597           /*
598            * No traffic and no events scheduled.  We can get rid of idle-heap.
599            */
600           int i;
601 
602           for (i = 0; i < p->idle_heap.elements; i++) {
603               struct dn_flow_queue *q = p->idle_heap.p[i].object;
604 
605               q->F = 0;
606               q->S = q->F + 1;
607           }
608           p->sum = 0;
609           p->V = 0;
610           p->idle_heap.elements = 0;
611     }
612 
613     /*
614      * If we are getting clocks from dummynet and if we are under credit,
615      * schedule the next ready event.
616      * Also fix the delivery time of the last packet.
617      */
618     if (p->numbytes < 0) { /* This implies bandwidth>0 */
619           dn_key t = 0; /* Number of ticks i have to wait */
620 
621           if (p->bandwidth > 0)
622               t = (p->bandwidth - 1 - p->numbytes) / p->bandwidth;
623           TAILQ_LAST(&p->p_queue, dn_pkt_queue)->output_time += t;
624           p->sched_time = curr_time;
625 
626           /*
627            * XXX should check errors on heap_insert, and drain the whole
628            * queue on error hoping next time we are luckier.
629            */
630           heap_insert(&wfq_ready_heap, curr_time + t, p);
631     }
632 
633     /*
634      * If the delay line was empty call transmit_event(p) now.
635      * Otherwise, the scheduler will take care of it.
636      */
637     if (p_was_empty)
638           transmit_event(p);
639 }
640 
641 static void
dn_expire_pipe_cb(struct dn_pipe * pipe,void * dummy __unused)642 dn_expire_pipe_cb(struct dn_pipe *pipe, void *dummy __unused)
643 {
644     if (pipe->idle_heap.elements > 0 &&
645           DN_KEY_LT(pipe->idle_heap.p[0].key, pipe->V)) {
646           struct dn_flow_queue *q = pipe->idle_heap.p[0].object;
647 
648           heap_extract(&pipe->idle_heap, NULL);
649           q->S = q->F + 1; /* Mark timestamp as invalid */
650           pipe->sum -= q->fs->weight;
651     }
652 }
653 
654 /*
655  * This is called once per tick, or dn_hz times per second.  It is used to
656  * increment the current tick counter and schedule expired events.
657  */
658 static void
dummynet(netmsg_t msg)659 dummynet(netmsg_t msg)
660 {
661     void *p;
662     struct dn_heap *h;
663     struct dn_heap *heaps[3];
664     int i;
665 
666     heaps[0] = &ready_heap;             /* Fixed-rate queues */
667     heaps[1] = &wfq_ready_heap;                   /* WF2Q queues */
668     heaps[2] = &extract_heap;           /* Delay line */
669 
670     /* Reply ASAP */
671     crit_enter();
672     lwkt_replymsg(&msg->lmsg, 0);
673     crit_exit();
674 
675     curr_time++;
676     for (i = 0; i < 3; i++) {
677           h = heaps[i];
678           while (h->elements > 0 && DN_KEY_LEQ(h->p[0].key, curr_time)) {
679               if (h->p[0].key > curr_time) {
680                     kprintf("-- dummynet: warning, heap %d is %d ticks late\n",
681                         i, (int)(curr_time - h->p[0].key));
682               }
683 
684               p = h->p[0].object;                 /* Store a copy before heap_extract */
685               heap_extract(h, NULL);    /* Need to extract before processing */
686 
687               if (i == 0)
688                     ready_event(p);
689               else if (i == 1)
690                     ready_event_wfq(p);
691               else
692                     transmit_event(p);
693           }
694     }
695 
696     /* Sweep pipes trying to expire idle flow_queues */
697     dn_iterate_pipe(dn_expire_pipe_cb, NULL);
698 }
699 
700 /*
701  * Unconditionally expire empty queues in case of shortage.
702  * Returns the number of queues freed.
703  */
704 static int
expire_queues(struct dn_flow_set * fs)705 expire_queues(struct dn_flow_set *fs)
706 {
707     int i, initial_elements = fs->rq_elements;
708 
709     if (fs->last_expired == time_uptime)
710           return 0;
711 
712     fs->last_expired = time_uptime;
713 
714     for (i = 0; i <= fs->rq_size; i++) { /* Last one is overflow */
715           struct dn_flow_queue *q, *qn;
716 
717           LIST_FOREACH_MUTABLE(q, &fs->rq[i], q_link, qn) {
718               if (!TAILQ_EMPTY(&q->queue) || q->S != q->F + 1)
719                     continue;
720 
721               /*
722                * Entry is idle, expire it
723                */
724               LIST_REMOVE(q, q_link);
725               kfree(q, M_DUMMYNET);
726 
727               KASSERT(fs->rq_elements > 0,
728                         ("invalid rq_elements %d", fs->rq_elements));
729               fs->rq_elements--;
730           }
731     }
732     return initial_elements - fs->rq_elements;
733 }
734 
735 /*
736  * If room, create a new queue and put at head of slot i;
737  * otherwise, create or use the default queue.
738  */
739 static struct dn_flow_queue *
create_queue(struct dn_flow_set * fs,int i)740 create_queue(struct dn_flow_set *fs, int i)
741 {
742     struct dn_flow_queue *q;
743 
744     if (fs->rq_elements > fs->rq_size * dn_max_ratio &&
745           expire_queues(fs) == 0) {
746           /*
747            * No way to get room, use or create overflow queue.
748            */
749           i = fs->rq_size;
750           if (!LIST_EMPTY(&fs->rq[i]))
751               return LIST_FIRST(&fs->rq[i]);
752     }
753 
754     q = kmalloc(sizeof(*q), M_DUMMYNET, M_INTWAIT | M_NULLOK | M_ZERO);
755     if (q == NULL)
756           return NULL;
757 
758     q->fs = fs;
759     q->hash_slot = i;
760     q->S = q->F + 1;   /* hack - mark timestamp as invalid */
761     TAILQ_INIT(&q->queue);
762 
763     LIST_INSERT_HEAD(&fs->rq[i], q, q_link);
764     fs->rq_elements++;
765 
766     return q;
767 }
768 
769 /*
770  * Given a flow_set and a pkt in last_pkt, find a matching queue
771  * after appropriate masking. The queue is moved to front
772  * so that further searches take less time.
773  */
774 static struct dn_flow_queue *
find_queue(struct dn_flow_set * fs,struct dn_flow_id * id)775 find_queue(struct dn_flow_set *fs, struct dn_flow_id *id)
776 {
777     struct dn_flow_queue *q;
778     int i = 0;
779 
780     if (!(fs->flags_fs & DN_HAVE_FLOW_MASK)) {
781           q = LIST_FIRST(&fs->rq[0]);
782     } else {
783           struct dn_flow_queue *qn;
784 
785           /* First, do the masking */
786           id->fid_dst_ip &= fs->flow_mask.fid_dst_ip;
787           id->fid_src_ip &= fs->flow_mask.fid_src_ip;
788           id->fid_dst_port &= fs->flow_mask.fid_dst_port;
789           id->fid_src_port &= fs->flow_mask.fid_src_port;
790           id->fid_proto &= fs->flow_mask.fid_proto;
791           id->fid_flags = 0; /* we don't care about this one */
792 
793           /* Then, hash function */
794           i = ((id->fid_dst_ip) & 0xffff) ^
795               ((id->fid_dst_ip >> 15) & 0xffff) ^
796               ((id->fid_src_ip << 1) & 0xffff) ^
797               ((id->fid_src_ip >> 16 ) & 0xffff) ^
798               (id->fid_dst_port << 1) ^ (id->fid_src_port) ^
799               (id->fid_proto);
800           i = i % fs->rq_size;
801 
802           /*
803            * Finally, scan the current list for a match and
804            * expire idle flow queues
805            */
806           searches++;
807           LIST_FOREACH_MUTABLE(q, &fs->rq[i], q_link, qn) {
808               search_steps++;
809               if (id->fid_dst_ip == q->id.fid_dst_ip &&
810                     id->fid_src_ip == q->id.fid_src_ip &&
811                     id->fid_dst_port == q->id.fid_dst_port &&
812                     id->fid_src_port == q->id.fid_src_port &&
813                     id->fid_proto == q->id.fid_proto &&
814                     id->fid_flags == q->id.fid_flags) {
815                     break; /* Found */
816               } else if (pipe_expire && TAILQ_EMPTY(&q->queue) &&
817                            q->S == q->F + 1) {
818                     /*
819                      * Entry is idle and not in any heap, expire it
820                      */
821                     LIST_REMOVE(q, q_link);
822                     kfree(q, M_DUMMYNET);
823 
824                     KASSERT(fs->rq_elements > 0,
825                               ("invalid rq_elements %d", fs->rq_elements));
826                     fs->rq_elements--;
827               }
828           }
829           if (q && LIST_FIRST(&fs->rq[i]) != q) { /* Found and not in front */
830               LIST_REMOVE(q, q_link);
831               LIST_INSERT_HEAD(&fs->rq[i], q, q_link);
832           }
833     }
834     if (q == NULL) {          /* No match, need to allocate a new entry */
835           q = create_queue(fs, i);
836           if (q != NULL)
837               q->id = *id;
838     }
839     return q;
840 }
841 
842 static int
red_drops(struct dn_flow_set * fs,struct dn_flow_queue * q,int len)843 red_drops(struct dn_flow_set *fs, struct dn_flow_queue *q, int len)
844 {
845     /*
846      * RED algorithm
847      *
848      * RED calculates the average queue size (avg) using a low-pass filter
849      * with an exponential weighted (w_q) moving average:
850      *    avg  <-  (1-w_q) * avg + w_q * q_size
851      * where q_size is the queue length (measured in bytes or * packets).
852      *
853      * If q_size == 0, we compute the idle time for the link, and set
854      *    avg = (1 - w_q)^(idle/s)
855      * where s is the time needed for transmitting a medium-sized packet.
856      *
857      * Now, if avg < min_th the packet is enqueued.
858      * If avg > max_th the packet is dropped. Otherwise, the packet is
859      * dropped with probability P function of avg.
860      */
861 
862     int64_t p_b = 0;
863     u_int q_size = (fs->flags_fs & DN_QSIZE_IS_BYTES) ? q->len_bytes : q->len;
864 
865     DPRINTF("\n%d q: %2u ", (int)curr_time, q_size);
866 
867     /* Average queue size estimation */
868     if (q_size != 0) {
869           /*
870            * Queue is not empty, avg <- avg + (q_size - avg) * w_q
871            */
872           int diff = SCALE(q_size) - q->avg;
873           int64_t v = SCALE_MUL((int64_t)diff, (int64_t)fs->w_q);
874 
875           q->avg += (int)v;
876     } else {
877           /*
878            * Queue is empty, find for how long the queue has been
879            * empty and use a lookup table for computing
880            * (1 - * w_q)^(idle_time/s) where s is the time to send a
881            * (small) packet.
882            * XXX check wraps...
883            */
884           if (q->avg) {
885               u_int t = (curr_time - q->q_time) / fs->lookup_step;
886 
887               q->avg = (t < fs->lookup_depth) ?
888                          SCALE_MUL(q->avg, fs->w_q_lookup[t]) : 0;
889           }
890     }
891     DPRINTF("avg: %u ", SCALE_VAL(q->avg));
892 
893     /* Should i drop? */
894 
895     if (q->avg < fs->min_th) {
896           /* Accept packet */
897           q->count = -1;
898           return 0;
899     }
900 
901     if (q->avg >= fs->max_th) { /* Average queue >=  Max threshold */
902           if (fs->flags_fs & DN_IS_GENTLE_RED) {
903               /*
904                * According to Gentle-RED, if avg is greater than max_th the
905                * packet is dropped with a probability
906                *    p_b = c_3 * avg - c_4
907                * where c_3 = (1 - max_p) / max_th, and c_4 = 1 - 2 * max_p
908                */
909               p_b = SCALE_MUL((int64_t)fs->c_3, (int64_t)q->avg) - fs->c_4;
910           } else {
911               q->count = -1;
912               kprintf("- drop\n");
913               return 1;
914           }
915     } else if (q->avg > fs->min_th) {
916           /*
917            * We compute p_b using the linear dropping function p_b = c_1 *
918            * avg - c_2, where c_1 = max_p / (max_th - min_th), and c_2 =
919            * max_p * min_th / (max_th - min_th)
920            */
921           p_b = SCALE_MUL((int64_t)fs->c_1, (int64_t)q->avg) - fs->c_2;
922     }
923     if (fs->flags_fs & DN_QSIZE_IS_BYTES)
924           p_b = (p_b * len) / fs->max_pkt_size;
925 
926     if (++q->count == 0) {
927           q->random = krandom() & 0xffff;
928     } else {
929           /*
930            * q->count counts packets arrived since last drop, so a greater
931            * value of q->count means a greater packet drop probability.
932            */
933           if (SCALE_MUL(p_b, SCALE((int64_t)q->count)) > q->random) {
934               q->count = 0;
935               DPRINTF("%s", "- red drop");
936               /* After a drop we calculate a new random value */
937               q->random = krandom() & 0xffff;
938               return 1;    /* Drop */
939           }
940     }
941     /* End of RED algorithm */
942     return 0; /* Accept */
943 }
944 
945 static void
dn_iterate_pipe(dn_pipe_iter_t func,void * arg)946 dn_iterate_pipe(dn_pipe_iter_t func, void *arg)
947 {
948     int i;
949 
950     for (i = 0; i < DN_NR_HASH_MAX; ++i) {
951           struct dn_pipe_head *pipe_hdr = &pipe_table[i];
952           struct dn_pipe *pipe, *pipe_next;
953 
954           LIST_FOREACH_MUTABLE(pipe, pipe_hdr, p_link, pipe_next)
955               func(pipe, arg);
956     }
957 }
958 
959 static void
dn_iterate_flowset(dn_flowset_iter_t func,void * arg)960 dn_iterate_flowset(dn_flowset_iter_t func, void *arg)
961 {
962     int i;
963 
964     for (i = 0; i < DN_NR_HASH_MAX; ++i) {
965           struct dn_flowset_head *fs_hdr = &flowset_table[i];
966           struct dn_flow_set *fs, *fs_next;
967 
968           LIST_FOREACH_MUTABLE(fs, fs_hdr, fs_link, fs_next)
969               func(fs, arg);
970     }
971 }
972 
973 static struct dn_pipe *
dn_find_pipe(int pipe_nr)974 dn_find_pipe(int pipe_nr)
975 {
976     struct dn_pipe_head *pipe_hdr;
977     struct dn_pipe *p;
978 
979     pipe_hdr = &pipe_table[DN_NR_HASH(pipe_nr)];
980     LIST_FOREACH(p, pipe_hdr, p_link) {
981           if (p->pipe_nr == pipe_nr)
982               break;
983     }
984     return p;
985 }
986 
987 static struct dn_flow_set *
dn_find_flowset(int fs_nr)988 dn_find_flowset(int fs_nr)
989 {
990     struct dn_flowset_head *fs_hdr;
991     struct dn_flow_set *fs;
992 
993     fs_hdr = &flowset_table[DN_NR_HASH(fs_nr)];
994     LIST_FOREACH(fs, fs_hdr, fs_link) {
995           if (fs->fs_nr == fs_nr)
996               break;
997     }
998     return fs;
999 }
1000 
1001 static struct dn_flow_set *
dn_locate_flowset(int pipe_nr,int is_pipe)1002 dn_locate_flowset(int pipe_nr, int is_pipe)
1003 {
1004     struct dn_flow_set *fs = NULL;
1005 
1006     if (!is_pipe) {
1007           fs = dn_find_flowset(pipe_nr);
1008     } else {
1009           struct dn_pipe *p;
1010 
1011           p = dn_find_pipe(pipe_nr);
1012           if (p != NULL)
1013               fs = &p->fs;
1014     }
1015     return fs;
1016 }
1017 
1018 /*
1019  * Dummynet hook for packets.  Below 'pipe' is a pipe or a queue
1020  * depending on whether WF2Q or fixed bw is used.
1021  *
1022  * pipe_nr          pipe or queue the packet is destined for.
1023  * dir              where shall we send the packet after dummynet.
1024  * m                the mbuf with the packet
1025  * fwa->oif         the 'ifp' parameter from the caller.
1026  *                  NULL in ip_input, destination interface in ip_output
1027  * fwa->ro          route parameter (only used in ip_output, NULL otherwise)
1028  * fwa->dst         destination address, only used by ip_output
1029  * fwa->rule        matching rule, in case of multiple passes
1030  * fwa->flags       flags from the caller, only used in ip_output
1031  */
1032 static int
dummynet_io(struct mbuf * m)1033 dummynet_io(struct mbuf *m)
1034 {
1035     struct dn_pkt *pkt;
1036     struct m_tag *tag;
1037     struct dn_flow_set *fs;
1038     struct dn_pipe *pipe;
1039     uint64_t len = m->m_pkthdr.len;
1040     struct dn_flow_queue *q = NULL;
1041     int is_pipe, pipe_nr;
1042 
1043     tag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
1044     pkt = m_tag_data(tag);
1045 
1046     is_pipe = pkt->dn_flags & DN_FLAGS_IS_PIPE;
1047     pipe_nr = pkt->pipe_nr;
1048 
1049     /*
1050      * This is a dummynet rule, so we expect a O_PIPE or O_QUEUE rule
1051      */
1052     fs = dn_locate_flowset(pipe_nr, is_pipe);
1053     if (fs == NULL)
1054           goto dropit;        /* This queue/pipe does not exist! */
1055 
1056     pipe = fs->pipe;
1057     if (pipe == NULL) { /* Must be a queue, try find a matching pipe */
1058           pipe = dn_find_pipe(fs->parent_nr);
1059           if (pipe != NULL) {
1060               fs->pipe = pipe;
1061           } else {
1062               kprintf("No pipe %d for queue %d, drop pkt\n",
1063                         fs->parent_nr, fs->fs_nr);
1064               goto dropit;
1065           }
1066     }
1067 
1068     q = find_queue(fs, &pkt->id);
1069     if (q == NULL)
1070           goto dropit;        /* Cannot allocate queue */
1071 
1072     /*
1073      * Update statistics, then check reasons to drop pkt
1074      */
1075     q->tot_bytes += len;
1076     q->tot_pkts++;
1077 
1078     if (fs->plr && krandom() < fs->plr)
1079           goto dropit;        /* Random pkt drop */
1080 
1081     if (fs->flags_fs & DN_QSIZE_IS_BYTES) {
1082           if (q->len_bytes > fs->qsize)
1083               goto dropit;    /* Queue size overflow */
1084     } else {
1085           if (q->len >= fs->qsize)
1086               goto dropit;    /* Queue count overflow */
1087     }
1088 
1089     if ((fs->flags_fs & DN_IS_RED) && red_drops(fs, q, len))
1090           goto dropit;
1091 
1092     TAILQ_INSERT_TAIL(&q->queue, pkt, dn_next);
1093     q->len++;
1094     q->len_bytes += len;
1095 
1096     if (TAILQ_FIRST(&q->queue) != pkt)  /* Flow was not idle, we are done */
1097           goto done;
1098 
1099     /*
1100      * If we reach this point the flow was previously idle, so we need
1101      * to schedule it.  This involves different actions for fixed-rate
1102      * or WF2Q queues.
1103      */
1104     if (is_pipe) {
1105           /*
1106            * Fixed-rate queue: just insert into the ready_heap.
1107            */
1108           dn_key t = 0;
1109 
1110           if (pipe->bandwidth)
1111               t = SET_TICKS(pkt, q, pipe);
1112 
1113           q->sched_time = curr_time;
1114           if (t == 0)         /* Must process it now */
1115               ready_event(q);
1116           else
1117               heap_insert(&ready_heap, curr_time + t, q);
1118     } else {
1119           /*
1120            * WF2Q:
1121            * First, compute start time S: if the flow was idle (S=F+1)
1122            * set S to the virtual time V for the controlling pipe, and update
1123            * the sum of weights for the pipe; otherwise, remove flow from
1124            * idle_heap and set S to max(F, V).
1125            * Second, compute finish time F = S + len/weight.
1126            * Third, if pipe was idle, update V = max(S, V).
1127            * Fourth, count one more backlogged flow.
1128            */
1129           if (DN_KEY_GT(q->S, q->F)) { /* Means timestamps are invalid */
1130               q->S = pipe->V;
1131               pipe->sum += fs->weight; /* Add weight of new queue */
1132           } else {
1133               heap_extract(&pipe->idle_heap, q);
1134               q->S = MAX64(q->F, pipe->V);
1135           }
1136           q->F = q->S + (len << MY_M) / (uint64_t)fs->weight;
1137 
1138           if (pipe->not_eligible_heap.elements == 0 &&
1139               pipe->scheduler_heap.elements == 0)
1140               pipe->V = MAX64(q->S, pipe->V);
1141 
1142           fs->backlogged++;
1143 
1144           /*
1145            * Look at eligibility.  A flow is not eligibile if S>V (when
1146            * this happens, it means that there is some other flow already
1147            * scheduled for the same pipe, so the scheduler_heap cannot be
1148            * empty).  If the flow is not eligible we just store it in the
1149            * not_eligible_heap.  Otherwise, we store in the scheduler_heap
1150            * and possibly invoke ready_event_wfq() right now if there is
1151            * leftover credit.
1152            * Note that for all flows in scheduler_heap (SCH), S_i <= V,
1153            * and for all flows in not_eligible_heap (NEH), S_i > V.
1154            * So when we need to compute max(V, min(S_i)) forall i in SCH+NEH,
1155            * we only need to look into NEH.
1156            */
1157           if (DN_KEY_GT(q->S, pipe->V)) {         /* Not eligible */
1158               if (pipe->scheduler_heap.elements == 0)
1159                     kprintf("++ ouch! not eligible but empty scheduler!\n");
1160               heap_insert(&pipe->not_eligible_heap, q->S, q);
1161           } else {
1162               heap_insert(&pipe->scheduler_heap, q->F, q);
1163               if (pipe->numbytes >= 0) {          /* Pipe is idle */
1164                     if (pipe->scheduler_heap.elements != 1)
1165                         kprintf("*** OUCH! pipe should have been idle!\n");
1166                     DPRINTF("Waking up pipe %d at %d\n",
1167                               pipe->pipe_nr, (int)(q->F >> MY_M));
1168                     pipe->sched_time = curr_time;
1169                     ready_event_wfq(pipe);
1170               }
1171           }
1172     }
1173 done:
1174     return 0;
1175 
1176 dropit:
1177     if (q)
1178           q->drops++;
1179     return ENOBUFS;
1180 }
1181 
1182 /*
1183  * Dispose all packets and flow_queues on a flow_set.
1184  * If all=1, also remove red lookup table and other storage,
1185  * including the descriptor itself.
1186  * For the one in dn_pipe MUST also cleanup ready_heap...
1187  */
1188 static void
purge_flow_set(struct dn_flow_set * fs,int all)1189 purge_flow_set(struct dn_flow_set *fs, int all)
1190 {
1191     int i;
1192 #ifdef INVARIANTS
1193     int rq_elements = 0;
1194 #endif
1195 
1196     for (i = 0; i <= fs->rq_size; i++) {
1197           struct dn_flow_queue *q;
1198 
1199           while ((q = LIST_FIRST(&fs->rq[i])) != NULL) {
1200               struct dn_pkt *pkt;
1201 
1202               while ((pkt = TAILQ_FIRST(&q->queue)) != NULL) {
1203                     TAILQ_REMOVE(&q->queue, pkt, dn_next);
1204                     ip_dn_packet_free(pkt);
1205               }
1206 
1207               LIST_REMOVE(q, q_link);
1208               kfree(q, M_DUMMYNET);
1209 
1210 #ifdef INVARIANTS
1211               rq_elements++;
1212 #endif
1213           }
1214     }
1215     KASSERT(rq_elements == fs->rq_elements,
1216               ("# rq elements mismatch, freed %d, total %d",
1217                rq_elements, fs->rq_elements));
1218     fs->rq_elements = 0;
1219 
1220     if (all) {
1221           /* RED - free lookup table */
1222           if (fs->w_q_lookup)
1223               kfree(fs->w_q_lookup, M_DUMMYNET);
1224 
1225           if (fs->rq)
1226               kfree(fs->rq, M_DUMMYNET);
1227 
1228           /*
1229            * If this fs is not part of a pipe, free it
1230            *
1231            * fs->pipe == NULL could happen, if 'fs' is a WF2Q and
1232            * - No packet belongs to that flow set is delivered by
1233            *   dummynet_io(), i.e. parent pipe is not installed yet.
1234            * - Parent pipe is deleted.
1235            */
1236           if (fs->pipe == NULL || (fs->pipe && fs != &fs->pipe->fs))
1237               kfree(fs, M_DUMMYNET);
1238     }
1239 }
1240 
1241 /*
1242  * Dispose all packets queued on a pipe (not a flow_set).
1243  * Also free all resources associated to a pipe, which is about
1244  * to be deleted.
1245  */
1246 static void
purge_pipe(struct dn_pipe * pipe)1247 purge_pipe(struct dn_pipe *pipe)
1248 {
1249     struct dn_pkt *pkt;
1250 
1251     purge_flow_set(&pipe->fs, 1);
1252 
1253     while ((pkt = TAILQ_FIRST(&pipe->p_queue)) != NULL) {
1254           TAILQ_REMOVE(&pipe->p_queue, pkt, dn_next);
1255           ip_dn_packet_free(pkt);
1256     }
1257 
1258     heap_free(&pipe->scheduler_heap);
1259     heap_free(&pipe->not_eligible_heap);
1260     heap_free(&pipe->idle_heap);
1261 }
1262 
1263 /*
1264  * Delete all pipes and heaps returning memory.
1265  */
1266 static void
dummynet_flush(void)1267 dummynet_flush(void)
1268 {
1269     struct dn_pipe_head pipe_list;
1270     struct dn_flowset_head fs_list;
1271     struct dn_pipe *p;
1272     struct dn_flow_set *fs;
1273     int i;
1274 
1275     lockmgr(&dn_lock, LK_EXCLUSIVE);
1276 
1277     /*
1278      * Prevent future matches...
1279      */
1280     LIST_INIT(&pipe_list);
1281     for (i = 0; i < DN_NR_HASH_MAX; ++i) {
1282           struct dn_pipe_head *pipe_hdr = &pipe_table[i];
1283 
1284           while ((p = LIST_FIRST(pipe_hdr)) != NULL) {
1285               LIST_REMOVE(p, p_link);
1286               LIST_INSERT_HEAD(&pipe_list, p, p_link);
1287               --dn_count;
1288           }
1289     }
1290 
1291     LIST_INIT(&fs_list);
1292     for (i = 0; i < DN_NR_HASH_MAX; ++i) {
1293           struct dn_flowset_head *fs_hdr = &flowset_table[i];
1294 
1295           while ((fs = LIST_FIRST(fs_hdr)) != NULL) {
1296               LIST_REMOVE(fs, fs_link);
1297               LIST_INSERT_HEAD(&fs_list, fs, fs_link);
1298               --dn_count;
1299           }
1300     }
1301 
1302     /* Free heaps so we don't have unwanted events */
1303     heap_free(&ready_heap);
1304     heap_free(&wfq_ready_heap);
1305     heap_free(&extract_heap);
1306 
1307     /*
1308      * Now purge all queued pkts and delete all pipes
1309      */
1310     /* Scan and purge all flow_sets. */
1311     while ((fs = LIST_FIRST(&fs_list)) != NULL) {
1312           LIST_REMOVE(fs, fs_link);
1313           purge_flow_set(fs, 1);
1314     }
1315 
1316     while ((p = LIST_FIRST(&pipe_list)) != NULL) {
1317           LIST_REMOVE(p, p_link);
1318           purge_pipe(p);
1319           kfree(p, M_DUMMYNET);
1320     }
1321 
1322     /*
1323      * Everything has been cleaned out, clear the run state.
1324      */
1325     KKASSERT(dn_count == 0);
1326     if (dn_running) {
1327               systimer_del(&dn_clock);
1328               dn_running = 0;
1329     }
1330     lockmgr(&dn_lock, LK_RELEASE);
1331 }
1332 
1333 /*
1334  * setup RED parameters
1335  */
1336 static int
config_red(const struct dn_ioc_flowset * ioc_fs,struct dn_flow_set * x)1337 config_red(const struct dn_ioc_flowset *ioc_fs, struct dn_flow_set *x)
1338 {
1339     int i;
1340 
1341     x->w_q = ioc_fs->w_q;
1342     x->min_th = SCALE(ioc_fs->min_th);
1343     x->max_th = SCALE(ioc_fs->max_th);
1344     x->max_p = ioc_fs->max_p;
1345 
1346     x->c_1 = ioc_fs->max_p / (ioc_fs->max_th - ioc_fs->min_th);
1347     x->c_2 = SCALE_MUL(x->c_1, SCALE(ioc_fs->min_th));
1348     if (x->flags_fs & DN_IS_GENTLE_RED) {
1349           x->c_3 = (SCALE(1) - ioc_fs->max_p) / ioc_fs->max_th;
1350           x->c_4 = (SCALE(1) - 2 * ioc_fs->max_p);
1351     }
1352 
1353     /* If the lookup table already exist, free and create it again */
1354     if (x->w_q_lookup) {
1355           kfree(x->w_q_lookup, M_DUMMYNET);
1356           x->w_q_lookup = NULL ;
1357     }
1358 
1359     if (red_lookup_depth == 0) {
1360           kprintf("net.inet.ip.dummynet.red_lookup_depth must be > 0\n");
1361           kfree(x, M_DUMMYNET);
1362           return EINVAL;
1363     }
1364     x->lookup_depth = red_lookup_depth;
1365     x->w_q_lookup = kmalloc(x->lookup_depth * sizeof(int),
1366                                   M_DUMMYNET, M_WAITOK);
1367 
1368     /* Fill the lookup table with (1 - w_q)^x */
1369     x->lookup_step = ioc_fs->lookup_step;
1370     x->lookup_weight = ioc_fs->lookup_weight;
1371 
1372     x->w_q_lookup[0] = SCALE(1) - x->w_q;
1373     for (i = 1; i < x->lookup_depth; i++)
1374           x->w_q_lookup[i] = SCALE_MUL(x->w_q_lookup[i - 1], x->lookup_weight);
1375 
1376     if (red_avg_pkt_size < 1)
1377           red_avg_pkt_size = 512;
1378     x->avg_pkt_size = red_avg_pkt_size;
1379 
1380     if (red_max_pkt_size < 1)
1381           red_max_pkt_size = 1500;
1382     x->max_pkt_size = red_max_pkt_size;
1383 
1384     return 0;
1385 }
1386 
1387 static void
alloc_hash(struct dn_flow_set * x,const struct dn_ioc_flowset * ioc_fs)1388 alloc_hash(struct dn_flow_set *x, const struct dn_ioc_flowset *ioc_fs)
1389 {
1390     int i, alloc_size;
1391 
1392     if (x->flags_fs & DN_HAVE_FLOW_MASK) {
1393           int l = ioc_fs->rq_size;
1394 
1395           /* Allocate some slots */
1396           if (l == 0)
1397               l = dn_hash_size;
1398 
1399           if (l < DN_MIN_HASH_SIZE)
1400               l = DN_MIN_HASH_SIZE;
1401           else if (l > DN_MAX_HASH_SIZE)
1402               l = DN_MAX_HASH_SIZE;
1403 
1404           x->rq_size = l;
1405     } else {
1406           /* One is enough for null mask */
1407           x->rq_size = 1;
1408     }
1409     alloc_size = x->rq_size + 1;
1410 
1411     x->rq = kmalloc(alloc_size * sizeof(struct dn_flowqueue_head),
1412                         M_DUMMYNET, M_WAITOK | M_ZERO);
1413     x->rq_elements = 0;
1414 
1415     for (i = 0; i < alloc_size; ++i)
1416           LIST_INIT(&x->rq[i]);
1417 }
1418 
1419 static void
set_flowid_parms(struct dn_flow_id * id,const struct dn_ioc_flowid * ioc_id)1420 set_flowid_parms(struct dn_flow_id *id, const struct dn_ioc_flowid *ioc_id)
1421 {
1422     id->fid_dst_ip = ioc_id->u.ip.dst_ip;
1423     id->fid_src_ip = ioc_id->u.ip.src_ip;
1424     id->fid_dst_port = ioc_id->u.ip.dst_port;
1425     id->fid_src_port = ioc_id->u.ip.src_port;
1426     id->fid_proto = ioc_id->u.ip.proto;
1427     id->fid_flags = ioc_id->u.ip.flags;
1428 }
1429 
1430 static void
set_fs_parms(struct dn_flow_set * x,const struct dn_ioc_flowset * ioc_fs)1431 set_fs_parms(struct dn_flow_set *x, const struct dn_ioc_flowset *ioc_fs)
1432 {
1433     x->flags_fs = ioc_fs->flags_fs;
1434     x->qsize = ioc_fs->qsize;
1435     x->plr = ioc_fs->plr;
1436     set_flowid_parms(&x->flow_mask, &ioc_fs->flow_mask);
1437     if (x->flags_fs & DN_QSIZE_IS_BYTES) {
1438           if (x->qsize > 1024 * 1024)
1439               x->qsize = 1024 * 1024;
1440     } else {
1441           if (x->qsize == 0 || x->qsize > 100)
1442               x->qsize = 50;
1443     }
1444 
1445     /* Configuring RED */
1446     if (x->flags_fs & DN_IS_RED)
1447           config_red(ioc_fs, x);        /* XXX should check errors */
1448 }
1449 
1450 /*
1451  * setup pipe or queue parameters.
1452  */
1453 
1454 static int
config_pipe(struct dn_ioc_pipe * ioc_pipe)1455 config_pipe(struct dn_ioc_pipe *ioc_pipe)
1456 {
1457     struct dn_ioc_flowset *ioc_fs = &ioc_pipe->fs;
1458     int error;
1459 
1460     /*
1461      * The config program passes parameters as follows:
1462      * bw bits/second (0 means no limits)
1463      * delay        ms (must be translated into ticks)
1464      * qsize        slots or bytes
1465      */
1466     ioc_pipe->delay = (ioc_pipe->delay * dn_hz) / 1000;
1467 
1468     /*
1469      * We need either a pipe number or a flow_set number
1470      */
1471     if (ioc_pipe->pipe_nr == 0 && ioc_fs->fs_nr == 0)
1472           return EINVAL;
1473     if (ioc_pipe->pipe_nr != 0 && ioc_fs->fs_nr != 0)
1474           return EINVAL;
1475 
1476     /*
1477      * Validate pipe number
1478      */
1479     if (ioc_pipe->pipe_nr > DN_PIPE_NR_MAX || ioc_pipe->pipe_nr < 0)
1480           return EINVAL;
1481 
1482     lockmgr(&dn_lock, LK_EXCLUSIVE);
1483     error = EINVAL;
1484 
1485     if (ioc_pipe->pipe_nr != 0) {       /* This is a pipe */
1486           struct dn_pipe *x, *p;
1487 
1488           /* Locate pipe */
1489           p = dn_find_pipe(ioc_pipe->pipe_nr);
1490 
1491           if (p == NULL) {    /* New pipe */
1492               x = kmalloc(sizeof(struct dn_pipe), M_DUMMYNET, M_WAITOK | M_ZERO);
1493               x->pipe_nr = ioc_pipe->pipe_nr;
1494               x->fs.pipe = x;
1495               TAILQ_INIT(&x->p_queue);
1496 
1497               /*
1498                * idle_heap is the only one from which we extract from the middle.
1499                */
1500               x->idle_heap.size = x->idle_heap.elements = 0;
1501               x->idle_heap.offset = __offsetof(struct dn_flow_queue, heap_pos);
1502           } else {
1503               int i;
1504 
1505               x = p;
1506 
1507               /* Flush accumulated credit for all queues */
1508               for (i = 0; i <= x->fs.rq_size; i++) {
1509                     struct dn_flow_queue *q;
1510 
1511                     LIST_FOREACH(q, &x->fs.rq[i], q_link)
1512                         q->numbytes = 0;
1513               }
1514           }
1515 
1516           x->bandwidth = ioc_pipe->bandwidth;
1517           x->numbytes = 0; /* Just in case... */
1518           x->delay = ioc_pipe->delay;
1519 
1520           set_fs_parms(&x->fs, ioc_fs);
1521 
1522           if (x->fs.rq == NULL) {       /* A new pipe */
1523               struct dn_pipe_head *pipe_hdr;
1524 
1525               alloc_hash(&x->fs, ioc_fs);
1526 
1527               pipe_hdr = &pipe_table[DN_NR_HASH(x->pipe_nr)];
1528               LIST_INSERT_HEAD(pipe_hdr, x, p_link);
1529               ++dn_count;
1530           }
1531     } else {        /* Config flow_set */
1532           struct dn_flow_set *x, *fs;
1533 
1534           /* Locate flow_set */
1535           fs = dn_find_flowset(ioc_fs->fs_nr);
1536 
1537           if (fs == NULL) {   /* New flow_set */
1538               if (ioc_fs->parent_nr == 0)         /* Need link to a pipe */
1539                     goto back;
1540 
1541               x = kmalloc(sizeof(struct dn_flow_set), M_DUMMYNET,
1542                               M_WAITOK | M_ZERO);
1543               x->fs_nr = ioc_fs->fs_nr;
1544               x->parent_nr = ioc_fs->parent_nr;
1545               x->weight = ioc_fs->weight;
1546               if (x->weight == 0)
1547                     x->weight = 1;
1548               else if (x->weight > 100)
1549                     x->weight = 100;
1550           } else {
1551               /* Change parent pipe not allowed; must delete and recreate */
1552               if (ioc_fs->parent_nr != 0 && fs->parent_nr != ioc_fs->parent_nr)
1553                     goto back;
1554               x = fs;
1555           }
1556 
1557           set_fs_parms(x, ioc_fs);
1558 
1559           if (x->rq == NULL) {          /* A new flow_set */
1560               struct dn_flowset_head *fs_hdr;
1561 
1562               alloc_hash(x, ioc_fs);
1563 
1564               fs_hdr = &flowset_table[DN_NR_HASH(x->fs_nr)];
1565               LIST_INSERT_HEAD(fs_hdr, x, fs_link);
1566               ++dn_count;
1567           }
1568     }
1569     error = 0;
1570 
1571     /*
1572      * We have at least one entry, set run state and start the systimer
1573      * poll if necessary.
1574      */
1575     if (dn_running == 0) {
1576           dn_running = 1;
1577           systimer_init_periodic_nq(&dn_clock, dummynet_clock, NULL, dn_hz);
1578     }
1579 
1580 back:
1581     lockmgr(&dn_lock, LK_RELEASE);
1582     return error;
1583 }
1584 
1585 /*
1586  * Helper function to remove from a heap queues which are linked to
1587  * a flow_set about to be deleted.
1588  */
1589 static void
fs_remove_from_heap(struct dn_heap * h,struct dn_flow_set * fs)1590 fs_remove_from_heap(struct dn_heap *h, struct dn_flow_set *fs)
1591 {
1592     int i = 0, found = 0;
1593 
1594     while (i < h->elements) {
1595           if (((struct dn_flow_queue *)h->p[i].object)->fs == fs) {
1596               h->elements--;
1597               h->p[i] = h->p[h->elements];
1598               found++;
1599           } else {
1600               i++;
1601           }
1602     }
1603     if (found)
1604           heapify(h);
1605 }
1606 
1607 /*
1608  * helper function to remove a pipe from a heap (can be there at most once)
1609  */
1610 static void
pipe_remove_from_heap(struct dn_heap * h,struct dn_pipe * p)1611 pipe_remove_from_heap(struct dn_heap *h, struct dn_pipe *p)
1612 {
1613     if (h->elements > 0) {
1614           int i;
1615 
1616           for (i = 0; i < h->elements; i++) {
1617               if (h->p[i].object == p) { /* found it */
1618                     h->elements--;
1619                     h->p[i] = h->p[h->elements];
1620                     heapify(h);
1621                     break;
1622               }
1623           }
1624     }
1625 }
1626 
1627 static void
dn_unref_pipe_cb(struct dn_flow_set * fs,void * pipe0)1628 dn_unref_pipe_cb(struct dn_flow_set *fs, void *pipe0)
1629 {
1630     struct dn_pipe *pipe = pipe0;
1631 
1632     if (fs->pipe == pipe) {
1633           kprintf("++ ref to pipe %d from fs %d\n",
1634                     pipe->pipe_nr, fs->fs_nr);
1635           fs->pipe = NULL;
1636           purge_flow_set(fs, 0);
1637     }
1638 }
1639 
1640 /*
1641  * Fully delete a pipe or a queue, cleaning up associated info.
1642  */
1643 static int
delete_pipe(const struct dn_ioc_pipe * ioc_pipe)1644 delete_pipe(const struct dn_ioc_pipe *ioc_pipe)
1645 {
1646     struct dn_pipe *p;
1647     int error;
1648 
1649     if (ioc_pipe->pipe_nr == 0 && ioc_pipe->fs.fs_nr == 0)
1650           return EINVAL;
1651     if (ioc_pipe->pipe_nr != 0 && ioc_pipe->fs.fs_nr != 0)
1652           return EINVAL;
1653 
1654     if (ioc_pipe->pipe_nr > DN_NR_HASH_MAX || ioc_pipe->pipe_nr < 0)
1655           return EINVAL;
1656 
1657     lockmgr(&dn_lock, LK_EXCLUSIVE);
1658 
1659     error = EINVAL;
1660     if (ioc_pipe->pipe_nr != 0) {       /* This is an old-style pipe */
1661           /* Locate pipe */
1662           p = dn_find_pipe(ioc_pipe->pipe_nr);
1663           if (p == NULL)
1664               goto back; /* Not found */
1665 
1666           /* Unlink from pipe hash table */
1667           LIST_REMOVE(p, p_link);
1668           --dn_count;
1669 
1670           /* Remove all references to this pipe from flow_sets */
1671           dn_iterate_flowset(dn_unref_pipe_cb, p);
1672 
1673           fs_remove_from_heap(&ready_heap, &p->fs);
1674           purge_pipe(p);      /* Remove all data associated to this pipe */
1675 
1676           /* Remove reference to here from extract_heap and wfq_ready_heap */
1677           pipe_remove_from_heap(&extract_heap, p);
1678           pipe_remove_from_heap(&wfq_ready_heap, p);
1679 
1680           kfree(p, M_DUMMYNET);
1681     } else {        /* This is a WF2Q queue (dn_flow_set) */
1682           struct dn_flow_set *fs;
1683 
1684           /* Locate flow_set */
1685           fs = dn_find_flowset(ioc_pipe->fs.fs_nr);
1686           if (fs == NULL)
1687               goto back; /* Not found */
1688 
1689           LIST_REMOVE(fs, fs_link);
1690           --dn_count;
1691 
1692           if ((p = fs->pipe) != NULL) {
1693               /* Update total weight on parent pipe and cleanup parent heaps */
1694               p->sum -= fs->weight * fs->backlogged;
1695               fs_remove_from_heap(&p->not_eligible_heap, fs);
1696               fs_remove_from_heap(&p->scheduler_heap, fs);
1697 #if 1     /* XXX should i remove from idle_heap as well ? */
1698               fs_remove_from_heap(&p->idle_heap, fs);
1699 #endif
1700           }
1701           purge_flow_set(fs, 1);
1702     }
1703     error = 0;
1704 
1705     /*
1706      * If there are no more pipes or flow-sets, clear the run state.
1707      */
1708     if (dn_count == 0 && dn_running) {
1709               systimer_del(&dn_clock);
1710               dn_running = 0;
1711     }
1712 back:
1713     lockmgr(&dn_lock, LK_RELEASE);
1714 
1715     return error;
1716 }
1717 
1718 /*
1719  * helper function used to copy data from kernel in DUMMYNET_GET
1720  */
1721 static void
dn_copy_flowid(const struct dn_flow_id * id,struct dn_ioc_flowid * ioc_id)1722 dn_copy_flowid(const struct dn_flow_id *id, struct dn_ioc_flowid *ioc_id)
1723 {
1724     ioc_id->type = ETHERTYPE_IP;
1725     ioc_id->u.ip.dst_ip = id->fid_dst_ip;
1726     ioc_id->u.ip.src_ip = id->fid_src_ip;
1727     ioc_id->u.ip.dst_port = id->fid_dst_port;
1728     ioc_id->u.ip.src_port = id->fid_src_port;
1729     ioc_id->u.ip.proto = id->fid_proto;
1730     ioc_id->u.ip.flags = id->fid_flags;
1731 }
1732 
1733 static void *
dn_copy_flowqueues(const struct dn_flow_set * fs,void * bp)1734 dn_copy_flowqueues(const struct dn_flow_set *fs, void *bp)
1735 {
1736     struct dn_ioc_flowqueue *ioc_fq = bp;
1737     int i, copied = 0;
1738 
1739     for (i = 0; i <= fs->rq_size; i++) {
1740           const struct dn_flow_queue *q;
1741 
1742           LIST_FOREACH(q, &fs->rq[i], q_link) {
1743               if (q->hash_slot != i) {  /* XXX ASSERT */
1744                     kprintf("++ at %d: wrong slot (have %d, "
1745                               "should be %d)\n", copied, q->hash_slot, i);
1746               }
1747               if (q->fs != fs) {                  /* XXX ASSERT */
1748                     kprintf("++ at %d: wrong fs ptr (have %p, should be %p)\n",
1749                               i, q->fs, fs);
1750               }
1751 
1752               copied++;
1753 
1754               ioc_fq->len = q->len;
1755               ioc_fq->len_bytes = q->len_bytes;
1756               ioc_fq->tot_pkts = q->tot_pkts;
1757               ioc_fq->tot_bytes = q->tot_bytes;
1758               ioc_fq->drops = q->drops;
1759               ioc_fq->hash_slot = q->hash_slot;
1760               ioc_fq->S = q->S;
1761               ioc_fq->F = q->F;
1762               dn_copy_flowid(&q->id, &ioc_fq->id);
1763 
1764               ioc_fq++;
1765           }
1766     }
1767 
1768     if (copied != fs->rq_elements) {    /* XXX ASSERT */
1769           kprintf("++ wrong count, have %d should be %d\n",
1770                     copied, fs->rq_elements);
1771     }
1772     return ioc_fq;
1773 }
1774 
1775 static void
dn_copy_flowset(const struct dn_flow_set * fs,struct dn_ioc_flowset * ioc_fs,u_short fs_type)1776 dn_copy_flowset(const struct dn_flow_set *fs, struct dn_ioc_flowset *ioc_fs,
1777                     u_short fs_type)
1778 {
1779     ioc_fs->fs_type = fs_type;
1780 
1781     ioc_fs->fs_nr = fs->fs_nr;
1782     ioc_fs->flags_fs = fs->flags_fs;
1783     ioc_fs->parent_nr = fs->parent_nr;
1784 
1785     ioc_fs->weight = fs->weight;
1786     ioc_fs->qsize = fs->qsize;
1787     ioc_fs->plr = fs->plr;
1788 
1789     ioc_fs->rq_size = fs->rq_size;
1790     ioc_fs->rq_elements = fs->rq_elements;
1791 
1792     ioc_fs->w_q = fs->w_q;
1793     ioc_fs->max_th = fs->max_th;
1794     ioc_fs->min_th = fs->min_th;
1795     ioc_fs->max_p = fs->max_p;
1796 
1797     dn_copy_flowid(&fs->flow_mask, &ioc_fs->flow_mask);
1798 }
1799 
1800 static void
dn_calc_pipe_size_cb(struct dn_pipe * pipe,void * sz)1801 dn_calc_pipe_size_cb(struct dn_pipe *pipe, void *sz)
1802 {
1803     size_t *size = sz;
1804 
1805     *size += sizeof(struct dn_ioc_pipe) +
1806                pipe->fs.rq_elements * sizeof(struct dn_ioc_flowqueue);
1807 }
1808 
1809 static void
dn_calc_fs_size_cb(struct dn_flow_set * fs,void * sz)1810 dn_calc_fs_size_cb(struct dn_flow_set *fs, void *sz)
1811 {
1812     size_t *size = sz;
1813 
1814     *size += sizeof(struct dn_ioc_flowset) +
1815                fs->rq_elements * sizeof(struct dn_ioc_flowqueue);
1816 }
1817 
1818 static void
dn_copyout_pipe_cb(struct dn_pipe * pipe,void * bp0)1819 dn_copyout_pipe_cb(struct dn_pipe *pipe, void *bp0)
1820 {
1821     char **bp = bp0;
1822     struct dn_ioc_pipe *ioc_pipe = (struct dn_ioc_pipe *)(*bp);
1823 
1824     /*
1825      * Copy flow set descriptor associated with this pipe
1826      */
1827     dn_copy_flowset(&pipe->fs, &ioc_pipe->fs, DN_IS_PIPE);
1828 
1829     /*
1830      * Copy pipe descriptor
1831      */
1832     ioc_pipe->bandwidth = pipe->bandwidth;
1833     ioc_pipe->pipe_nr = pipe->pipe_nr;
1834     ioc_pipe->V = pipe->V;
1835     /* Convert delay to milliseconds */
1836     ioc_pipe->delay = (pipe->delay * 1000) / dn_hz;
1837 
1838     /*
1839      * Copy flow queue descriptors
1840      */
1841     *bp += sizeof(*ioc_pipe);
1842     *bp = dn_copy_flowqueues(&pipe->fs, *bp);
1843 }
1844 
1845 static void
dn_copyout_fs_cb(struct dn_flow_set * fs,void * bp0)1846 dn_copyout_fs_cb(struct dn_flow_set *fs, void *bp0)
1847 {
1848     char **bp = bp0;
1849     struct dn_ioc_flowset *ioc_fs = (struct dn_ioc_flowset *)(*bp);
1850 
1851     /*
1852      * Copy flow set descriptor
1853      */
1854     dn_copy_flowset(fs, ioc_fs, DN_IS_QUEUE);
1855 
1856     /*
1857      * Copy flow queue descriptors
1858      */
1859     *bp += sizeof(*ioc_fs);
1860     *bp = dn_copy_flowqueues(fs, *bp);
1861 }
1862 
1863 static int
dummynet_get(struct dn_sopt * dn_sopt)1864 dummynet_get(struct dn_sopt *dn_sopt)
1865 {
1866     char *buf, *bp;
1867     size_t size = 0;
1868 
1869     /*
1870      * Compute size of data structures: list of pipes and flow_sets.
1871      */
1872     dn_iterate_pipe(dn_calc_pipe_size_cb, &size);
1873     dn_iterate_flowset(dn_calc_fs_size_cb, &size);
1874 
1875     /*
1876      * Copyout pipe/flow_set/flow_queue
1877      */
1878     bp = buf = kmalloc(size, M_TEMP, M_WAITOK | M_ZERO);
1879     dn_iterate_pipe(dn_copyout_pipe_cb, &bp);
1880     dn_iterate_flowset(dn_copyout_fs_cb, &bp);
1881 
1882     /* Temp memory will be freed by caller */
1883     dn_sopt->dn_sopt_arg = buf;
1884     dn_sopt->dn_sopt_arglen = size;
1885     return 0;
1886 }
1887 
1888 /*
1889  * Handler for the various dummynet socket options (get, flush, config, del)
1890  */
1891 static int
dummynet_ctl(struct dn_sopt * dn_sopt)1892 dummynet_ctl(struct dn_sopt *dn_sopt)
1893 {
1894     int error = 0;
1895 
1896     switch (dn_sopt->dn_sopt_name) {
1897     case IP_DUMMYNET_GET:
1898           error = dummynet_get(dn_sopt);
1899           break;
1900 
1901     case IP_DUMMYNET_FLUSH:
1902           dummynet_flush();
1903           break;
1904 
1905     case IP_DUMMYNET_CONFIGURE:
1906           KKASSERT(dn_sopt->dn_sopt_arglen == sizeof(struct dn_ioc_pipe));
1907           error = config_pipe(dn_sopt->dn_sopt_arg);
1908           break;
1909 
1910     case IP_DUMMYNET_DEL:     /* Remove a pipe or flow_set */
1911           KKASSERT(dn_sopt->dn_sopt_arglen == sizeof(struct dn_ioc_pipe));
1912           error = delete_pipe(dn_sopt->dn_sopt_arg);
1913           break;
1914 
1915     default:
1916           kprintf("%s -- unknown option %d\n", __func__, dn_sopt->dn_sopt_name);
1917           error = EINVAL;
1918           break;
1919     }
1920     return error;
1921 }
1922 
1923 static void
dummynet_clock(systimer_t info __unused,int in_ipi __unused,struct intrframe * frame __unused)1924 dummynet_clock(systimer_t info __unused, int in_ipi __unused,
1925     struct intrframe *frame __unused)
1926 {
1927     KASSERT(mycpuid == ip_dn_cpu,
1928               ("dummynet systimer comes on cpu%d, should be %d!",
1929                mycpuid, ip_dn_cpu));
1930 
1931     crit_enter();
1932     if (DUMMYNET_LOADED && (dn_netmsg.lmsg.ms_flags & MSGF_DONE))
1933           lwkt_sendmsg_oncpu(netisr_cpuport(mycpuid), &dn_netmsg.lmsg);
1934     crit_exit();
1935 }
1936 
1937 static int
sysctl_dn_hz(SYSCTL_HANDLER_ARGS)1938 sysctl_dn_hz(SYSCTL_HANDLER_ARGS)
1939 {
1940     int error, val, origcpu;
1941 
1942     val = dn_hz;
1943     error = sysctl_handle_int(oidp, &val, 0, req);
1944     if (error || req->newptr == NULL)
1945           return error;
1946     if (val <= 0)
1947           return EINVAL;
1948     else if (val > DN_CALLOUT_FREQ_MAX)
1949           val = DN_CALLOUT_FREQ_MAX;
1950 
1951     origcpu = mycpuid;
1952     lwkt_migratecpu(ip_dn_cpu);
1953 
1954     lockmgr(&dn_lock, LK_EXCLUSIVE);
1955     crit_enter();
1956     dn_hz = val;
1957     if (dn_running)
1958               systimer_adjust_periodic(&dn_clock, val);
1959     crit_exit();
1960     lockmgr(&dn_lock, LK_RELEASE);
1961 
1962     lwkt_migratecpu(origcpu);
1963 
1964     return 0;
1965 }
1966 
1967 static void
ip_dn_init_dispatch(netmsg_t msg)1968 ip_dn_init_dispatch(netmsg_t msg)
1969 {
1970     int i, error = 0;
1971 
1972     KASSERT(mycpuid == ip_dn_cpu,
1973               ("%s runs on cpu%d, instead of cpu%d", __func__,
1974                mycpuid, ip_dn_cpu));
1975 
1976     crit_enter();
1977 
1978     if (DUMMYNET_LOADED) {
1979           kprintf("DUMMYNET already loaded\n");
1980           error = EEXIST;
1981           goto back;
1982     }
1983 
1984     kprintf("DUMMYNET initialized (011031)\n");
1985 
1986     for (i = 0; i < DN_NR_HASH_MAX; ++i)
1987           LIST_INIT(&pipe_table[i]);
1988 
1989     for (i = 0; i < DN_NR_HASH_MAX; ++i)
1990           LIST_INIT(&flowset_table[i]);
1991 
1992     ready_heap.size = ready_heap.elements = 0;
1993     ready_heap.offset = 0;
1994 
1995     wfq_ready_heap.size = wfq_ready_heap.elements = 0;
1996     wfq_ready_heap.offset = 0;
1997 
1998     extract_heap.size = extract_heap.elements = 0;
1999     extract_heap.offset = 0;
2000 
2001     ip_dn_ctl_ptr = dummynet_ctl;
2002     ip_dn_io_ptr = dummynet_io;
2003 
2004     netmsg_init(&dn_netmsg, NULL, &netisr_adone_rport,
2005                     0, dummynet);
2006 
2007     KKASSERT(dn_running == 0);
2008 #if 0
2009     /* REMOVED, initialized on first insertion */
2010     systimer_init_periodic_nq(&dn_clock, dummynet_clock, NULL, dn_hz);
2011 #endif
2012 
2013 back:
2014     crit_exit();
2015     lwkt_replymsg(&msg->lmsg, error);
2016 }
2017 
2018 static int
ip_dn_init(void)2019 ip_dn_init(void)
2020 {
2021     struct netmsg_base smsg;
2022 
2023     if (ip_dn_cpu >= ncpus) {
2024           kprintf("%s: CPU%d does not exist, switch to CPU0\n",
2025                     __func__, ip_dn_cpu);
2026           ip_dn_cpu = 0;
2027     }
2028 
2029     netmsg_init(&smsg, NULL, &curthread->td_msgport,
2030                     0, ip_dn_init_dispatch);
2031     lwkt_domsg(netisr_cpuport(ip_dn_cpu), &smsg.lmsg, 0);
2032     return smsg.lmsg.ms_error;
2033 }
2034 
2035 #ifdef KLD_MODULE
2036 
2037 static void
ip_dn_stop_dispatch(netmsg_t msg)2038 ip_dn_stop_dispatch(netmsg_t msg)
2039 {
2040     crit_enter();
2041 
2042     dummynet_flush();
2043 
2044     ip_dn_ctl_ptr = NULL;
2045     ip_dn_io_ptr = NULL;
2046     KKASSERT(dn_running == 0);
2047 
2048     crit_exit();
2049     lwkt_replymsg(&msg->lmsg, 0);
2050 }
2051 
2052 
2053 static void
ip_dn_stop(void)2054 ip_dn_stop(void)
2055 {
2056     struct netmsg_base smsg;
2057 
2058     netmsg_init(&smsg, NULL, &curthread->td_msgport,
2059                     0, ip_dn_stop_dispatch);
2060     lwkt_domsg(netisr_cpuport(ip_dn_cpu), &smsg.lmsg, 0);
2061 
2062     netmsg_service_sync();
2063 }
2064 
2065 #endif    /* KLD_MODULE */
2066 
2067 static int
dummynet_modevent(module_t mod,int type,void * data)2068 dummynet_modevent(module_t mod, int type, void *data)
2069 {
2070     switch (type) {
2071     case MOD_LOAD:
2072           return ip_dn_init();
2073 
2074     case MOD_UNLOAD:
2075 #ifndef KLD_MODULE
2076           kprintf("dummynet statically compiled, cannot unload\n");
2077           return EINVAL;
2078 #else
2079           ip_dn_stop();
2080 #endif
2081           break;
2082 
2083     default:
2084           break;
2085     }
2086     return 0;
2087 }
2088 
2089 static moduledata_t dummynet_mod = {
2090     "dummynet",
2091     dummynet_modevent,
2092     NULL
2093 };
2094 DECLARE_MODULE(dummynet, dummynet_mod, SI_SUB_PROTO_END, SI_ORDER_ANY);
2095 MODULE_VERSION(dummynet, 1);
2096